Shell roof construction



R. A. ROSE ETAL SHELL ROOF CONSTRUCTION Jan. 4, 1966 Filed March 2o,1963 4 Sheets-Sheet l INM @wij

A 1 mi /7/'6/70/"0 F056 and BY @eff/"0m 5 Wam/7cm;

INVENTORS.

IE- Z @a Wo/Wea Jan. 4, 1966 R. A. RosE ETAL. 3,226,892

SHELL ROOF CONSTRUCTION Filed March 20, 1963 4 Sheets-Sheet 2 Jan. 4,1966 R. A. Rose ETAL 3,226,892

SHELL ROOF CONSTRUCTION Filed March 20, 1963 4 Sheets-Sheet 3 [[1INVENTORS. I IE Efe/70rd A? H05@ 0/70 BY 9e/#0m 5 WamS/mw Jan. 4, 1966R. A. ROSE ETAL SHELL ROOF CONSTRUCTION 4 Sheets-Sheet 4 Filed March 20,1965 INVENTORAS` Richard/4. R05@ cmo 5e/"fram Wa/Maw J4/L Enf/fn@ UnitedStates Patent C) 3,226,892 SHELL ROF CONSTRUCTION Richard A. Rose, 1545Coilins Ave., Miami Beach, Fla., and Bertram S. Warshaw, 255 UniversityDrive, Coral Gables, Fla. t

Filed Mar. 20, 1963, Ser. No. 266,643 4 Claims. (Cl. 52-80) The presentinvention relates to shell structures and more particularly to a new andimproved method of reinforcement employed in the construction of shelltype roofs.

IThe design and construction of shell structures has increased in recentyears. Y

Although the principal material used has been steel reinforced concrete,an increasing variety of `other materials `is becoming available, amongwhich are plastics and metal alloys. The number of sizes and shapes ofthis type of structure is virtually unlimited. For ease of analysis anddesign, however, those forms whichlend themselves to less complexmathematical expressions have most often p been used, i.e. spheres,paraboloids, ellipses, conoids, hyperboloids.

Because of the great flexibility in size `and shape, the functional andaesthetic potential of shell structures is tremendous. The economicpotential is `also great because, in its final condition, the shellrequires a minimum of material. This economi-c` potential has not fullybeen realized due to the fact that no really practical method ofconstruction, especially for roofs, has as yet, been `devised but whichit is a main object of the instant invention to accomplish. y

All methods of shell construction utilized thus far employ -an externalmeans for supporting the shell during its erection. These methods haveincluded wood frames, earth mounds, balloons, cranes, etc. The `formsand supports must be carefully laid out and constructed in the field.The materials comprising the shell itself are then placed. Finally,after waiting a period of time for the shell materials to develop theirstrength, these extern-al forms or supports, must be carefully removed.This involves a great deal of labor and material, most of which, is in asense, wasted, since it does not contribute to the function of the shellin its final form.

To provide a new method for `the design and construction of shellstructures requiring no external means of support, and which effects.great economies in the erection of these structures, as well asoffering other advantages to be described, is an important object of theinvention.`

Shells are composed 'basicallyof two structural ele- `ments which, whenplaced together in the desired shape and form, interact with eachotherso as to give stability to the structure as a whole.` One of theseelements is the shell membrane. This must usually be capable ofwithstanding direct compressivel forces, the material most often usedfor this membrane being concrete or plastic. The other basicshellelement is the reinforcing, usually a metal or rigid-ized plastic,the function of which is to impart to the shell the means of resistingbending, twisting tension and temperature stresses.

In the design of the shell, according to our new and improved method,the major bending and torsional stresses occur at the boundary orperimeter portions of the shell. The heaviest shell reinforcing is,therefore, at these locations. It is 'another object of the invention toprovide such reinforcing by means of a series of space frames capable ofsupporting the weight of -all materials in the shell itself.

Reinforcing within the shell proper is needed primarily to withstandtension and temperature stresses. This reinforcing is designed as anauxiliary support system and it 3,2%,892 Patented Jan. d, 1966 ice is afurther object of the invention to provide a system of this characterwhich, in conjunction with the space frames, determines the shape anddimensions of the shell.

A further object of lthe invention is the inclusion in the auxiliarysupport system of means such as metal lath, wire or plastic fabric whichcan of itself contain and support the membrane material in its initialstate.

And a still further object of the invention is the provision of a shellstructure in which reinforcement such as above described can to a largeextent be prefabricated in parts and assembled in the field, all ofwhich leads to advantages relating to establishment of the outer limitsof the shell 'and more accurate dimensional control.

Since there is no external falsework or supports to be removed, andconsequently no waiting time while the membrane cures, whateverconstruction is to take place under or within the shell, can proceedimmediately without any delay, this being a further and important objectof the invention. f

And, a still further object of the invention is the advantage obtainedin the virtual elimination of damaging secondary stresses anddeformations. In an externally supported shell a stress pattern isdeveloped during construction, which is changed with relative suddennessupon removal of the external supports. With the method described here,`the stress patterns developed du-ring construction are similar to thoseof the final design and function. Deformations can be seen andcompensated for as construction progresses, since the lack of externalsupports permits these deformations to manifest themselves at a timewhen they are most easily corrected.

These, and `other objects and advantages of the invention will be made.apparent from the following more detailed description, taken inconnection With the accompanying drawings, and particularly defined inthe appended claims.

` The drawings are as follows:

FIGURE l is a plan view showing the corner abutment footings for thefour arched sides of a shell roof constructed in accordance with theinvention, and the floor slab of a building structure to be erectedunder the roof the latter being shown only in dotted line.

FIGURE 2 is a plan view illustrating tension ring placing and shellcorner reinforcement.

FIGURE 3 shows the shell roof in elevation, the View lbeing diagonallyof the abutment footings.

`FIGURE 6 is au elevation of the roof as viewed from` one side, aportion of the shell being broken away to show parts of the auxiliarysupport system.

FIGURE 7 `is an enlarged sectional detail similar to FIGURE 4, butthrough the shell roof only, and showin additional elements of the shellreinforcement.

`FIGURE 8 is a joint detail of the space frame shown in front elevation.

FIGURE 9 is a sectional View on line 9 9, FIG- URE 6.

FIGURE 10 is an enlarged detail in side view of the connection between ashell supporting tube and the space frame.

FIGURES 11A, 11B and 11C are details in plane view of supporting tubeconnectors at designations A, B, and C respectively, of FIGURE 5.

FIGURE 12 is a side view of the tube connector seen in FIGURE 11A.

FIGURE `13 is a side view of a support tube section.

Similar reference numerals refer to similar parts throughout thedrawing.

Numeral 1 represents generally a concrete shell providing a dome rooffor a structure to be erected under the roof, the floor slab 2 only ofsuch a structure being shown.

The shell 1 is squared along chord lines 3. This results in the roofbeing four sides and with each side forming an arch 4, the outer facesof these arches being coincident with the lines 3.

At the four corners of the arched sides the roof 1 terminates ingradually narrowing leg portions 5 supported as illustrated in FIGURES3, 4, and 6, above finished grade line 6, upo'n abutment footings 7.These footings 7, are shown connected through strap anchors 8 with thefoundation wall 9 upon which the floor slab 2 is built. And, as seen inFIGURE 4, the portions of arches 4 termihating at each abutment 7 arereinforced by dowels cz in accordance with standard practice.

The arches 4 define the perimeter of the shell 1 and the method ofconstruction, according to the present invention, requires that theperimeter reinforcing be designed as a series of space frames capable ofsupporting the weight of materials in the shell. Consequently theskeleton frame structures outline and give shape to the arches. Thespace frames are preferably Prefabricated in sections that can readilybe joined together in the field.

For each arch 4 there are two similar space frame sections 10, each suchsection includes a plurality, five in this instance, of reinforcing bars11 paralleling the curvature of the arch. These bars 11, as shown inFIG- URE 9, are rigidly held in spaced triangular relation by radialties 12 and 13 and trussed ties 14.

The bars 11, at one end of each frame section 10, terminate at the footof the arch, their other ends being welded to a wide face of a buttplate 15. The plates 15, 15, of each pair of frame sections 10, abuteach other and are secured together by suitable fastening means, such asthe bolts 15a on which nuts 15b are threaded.

Alignment cables 29 are connected to opposite points on the space framesto maintain the space frames in vertical alignment during placement ofthe shell membrane.

The next step in our method of shell construction is the erection of theauxiliary support system which provides the reinforcing elements neededprimarily t0 withstand tension and stresses within the shell proper.This reinforcement is so designed that, in conjunction with the spaceframes, the shape and dimensions of the shell are determined.

The just above mentioned support system includes a plurality of archedtubes 16, extending from the frame sections l@ aligned with one arch 4to corresponding points on the like sections outlining the oppositearch. Similarly, the space framing outlining the other two arches 4, isconnected. This arrangement of arched tubes 16, forms the grid or steelcentering pattern shown diagrammaticaliy in FIGURE 5. The arched tubes16 are preferably made of metal or plastic and, because of their lengthand curvature, are in sections which can be more accurate if precut andthen assembled in the field.

At arched tube crossings A and C, FIGURE 5, the arched tubes 16, havetelescopic connection with tubular connectors 17 and 13, respectively,made in the form of crosses as seen in FIGURES 11A, 11C and 12. Atcrossings B the connectors 19 are T-shape as in FIG- URE llB. This meansof connection support for the arched tubes 16, adds strength to the gridand holds it in shape.

The tubular connections 17, 18 and 19 also enable the structure to havea minimum of thickness and therefore a minimum of material and weight.

The grid formed by the crossed arched tubes 15, is supported by thespace frame sections 10 in the manner shown in FIGURE 10, the ends ofthe arched tubes 16 having telescopic connection with tubular sleeves20, between which and a plate 21, for each connection, the two uppermostand aligned -bars 11a of the space frame are clamped by bolts 22. A bolt23 extended through openings in the tubular bar 16 and its respectivesleeve 20 retains the two members in proper relative adjustment.

As further reinforcement a series of concentrically arrange-d tensionrings formed of bars 24 encircle the shell above but in proximity to thespace frame sections 10. Also a plurality of upwardly diverging bars 2Scrossed by segmental bars 26, see FIGURE 2, may be provided asadditional reinforcement for the leg portions 5 of the shell 1. Therings 24 and bars 25 and 26, would be retained in place by wires orother means attaching them to fixed parts such as the bars 16, theseattachments not being shown but well known in the art.

It may also be added that cables 30 in FIGURE 4A as shown, cansupplement, or replace, the tubing 16 should the curvature of the shell1 be reversed from that `shown in the illustrated dome 1, i.e. curveddownward, as in FIGURE 4A, which shows a hyperbolic paraboloid. FIGURE4A illustrates one type of downwardly curved shell. In FIGURE 4A cables30 support latticed material or mesh 27a to which concrete or otherplastic is applied in the same manner as above for other shapes.

The auxiliary support system also includes covering the reinforcingframework thus far described with metal lath, wire lor plastic fabricwhich can of itself contain and support the membrane forming material inits initial state, this covering material being indicated at 27' inFIGURES 6 and 7. The shell roof 1, at this stage of construction hasbecome a latticed structure conforming to the desired shell conguration.

The final step in the instant construction method is applying themembrane material 28 to the latticed material 2?' by spraying, spreadingor pouring, the membrane when cured providing coverage of predeterminedthickness to the entire reinforcing framework.

This membrane may be composed of pneumatcally applied concrete,plastics, such as styrene, polyvinyl, fiberglass, urethene, asphalt, orother similar materials, used by themselves or in combination.

The particular spherical dome and hyperbolic paraboloid presented hereare but two applications of this invention for the construction ofshells. The invention is also applicable in the design and constructionof any size shell of any other mathematically expressible shape such asparaboloids, hyperboloids, conoids, elliptoids, barrel vaults, fiatplates, folded plates, etc.

Since there is no external falsework or supports to be removed, andconsequently no waiting time while the membrane cures, whateverconstruction is to take place under or within the shell, can proceedimmediately with-- out any delay.

We claim:

1. A shell structure requiring no false work, framework or externalsupports which includes, in combination with footing abutments,

an arched shell comprising arched space frame members supporting theweight of materials forming the shell itself and supported at their endsupon said abutments,

additional members including arched members and members crossing saidarched members forming an open grid connected between said arched spaceframe members and supported thereby,

a lattice covering for said arched members and said arched space framemembers conforming to the desired shell configuration,

and means embedding said arched members and arched space frame membersforming said shell thereby enabling said structure to carry the totaldesign loads while acting in conjunction with said shell supportingspace frame members because of stress induced within said means.

2. The shell structure of claim 1, wherein said means embedding saidarched space frame members, and said additional members is aconcreterr'raterial.

3. The shell structure of cl-aimlvl, further characterized by saidarched space frame merfibers forming each arch being in twoprefabricated sectijfns, each such section including a plurality ofparallel bavrwsheld in spaced relation by tie and truss rods, said barseach being attac-hed at one of their ends to a butt plate, and said buttplate from each of tv vo sections being boltedtogether.

4. The shell structure of claim 1, further characterized by said archedspace frame members positioned to outline the perimeter portions of saidshell.

References Cited by the Examiner UNITED STATES PATENTS `2,666,5 071/1954 Ruark. 2,928,360 3/1960 Heine. 2,948,047 8/ 1960 Peeler et al.2,984,944 5/1961 Sapp.

3,051,185 8/1962 Reynolds 135--3 3,092,932 6/1963 WlSOIl.

u FOREIGN PATENTS 1,218,498 12/1959 France. i 1,191,776 4/1959 France.

713,972 8/ 1954 Great Britain.

748,104 l4/ 1956 Great Britain.

843,529 8/1960 Great Briain.

362,649 8/ 1938 Italy.

548,146 9/ 1956 Italy.

OTHER REFERENCES American Builder (publication) of November 1961, p. 18

1. A SHELL STRUCUTURE REQUIRING NO FALSE WORK, FRAMEWORK OR EXTERNALSUPPORTS WHICH INCLUDES, IN COMBINATION WITH FOOTING ABUTMENTS, ANARCHED SHELL COMPRISING ARCHED SPACE FRAME MEMBERS SUPPORTING THE WEIGHTOF MATERIALS FORMING THE SHELL ITSELF AND SUPPORTED AT THEIR ENDS UPONSAID ABUTMENTS, ADDITIONAL MEMBERS INCLUDING ARCHED MEMBERS AND MEMBERSCROSSING SAID ARCHED MEMBERS FORMING AN OPEN GRID CONNECTED BETWEEN SAIDARCHED SPACE FRAME MEMBERS ARE SUPPORTED THEREBY, A LATTICE COVERING FORSAID ARCHED MEMBERS AND SAID ARCHED SPACE FRAME MEMBERS CONFORMING TOTHE DESIRED SHELL CONFIGURATION, AND MEANS EMBEDDING SAID ARCHED MEMBERSAND ARCHED SPACE FRAME MEMBERS FORMING SAID SHELL THEREBY ENABLING SAIDSTRUCTURE TO CARRY THE TOTAL DESIGN LOADS WHILE ACTING IN CONJUNCTIONWITH SAID SHELL SUPPORTING SPACE FRAME MEMBERS BECAUSE OF STRESS INDUCEDWITHIN SAID MEANS.